Search PubMed⌕ Search

Biomedical subjects

S Feldman

Publications and source records attributed to S Feldman.

At least 397 records · Page 22Linked to original sources
PubMed1975

Effect of cortisol on the excitability of limbic structures of the brain in freely moving rats.

The effects of cortisol on the excitability of the dorsal hippocampus, septum, hypothalamus and the pontine reticular formation in unrestrained, unanesthetized rats with permanently-implanted electrodes were investigated. The hormone produced a slowing in the spontaneous activity in these regions. The stimulation of the septum, hypothalamus and reticular formation had no appreciable influence on the local or propagated electrical activity of the brain after cortisol injection; however in 14 out of 29 experiments hippocampal stimulation with the same voltages as before cortisol administration, induced generalized convulsive activity. The attacks consisted of high-voltage spikes and slow-wave activity and were followed by a post-seizure exhaustion in the hippocampus. In half of the rats behavioral convulsions also appeared. The convulsive effects of cortisol on the brain are briefly reviewed and the specificity of hippocampal involvement in the present experiments is emphasized. The possible significance of the present findings in relation to the feedback of glucocorticoids on the brain, in the regulation of ACTH secretion, is discussed. The experiments described may also contribute to our understanding of the mechanisms of the convulsive effects of cortisol on the brain.

Animals↗
PubMed1975

Hamartoma and renal transplant implications.

A 19-year-old woman with tuberous sclerosis, bilateral renal hamartomas and polycystic kidneys required separate nephrectomies for severe hemorrhages 6 months apart. The case is presented, the diagnoses of the disease in relation to a negative family history are considered and the importance of early diagnosis in a potential transplant recipient and the use of leukocyte-free transufusions are discussed.

Adenoma↗
PubMed1975

Evaluation of topical polyinosinic acid-polycytidylic acid in treatment of localized herpes zoster in children with cancer: a randomized, double-blind controlled study.

Twenty-four children with cancer and localized herpes zoster were randomized to receive either topical polyinosinic acid-polycytidylic acid [poly(I:C)] or a saline placebo. Solutions containing 1.0 or 2.5 mg of drug per ml were applied to the lesions every 3 h, seven times a day for 7 consecutive days. Serial, standardized color photographs were used to evaluate the progression of lesions and maximum percentage of dermatome involvement. In patients receiving poly(I:C), the median days of new lesions after therapy was 2.0 days as opposed to 3.5 days in placebo-treated patients. This difference was not statistically significant. Moreover, the total median days of lesions and percentage of dermatome involvement were similar in both groups, as were complications. Neither the concentration nor the total dose of drug was related to the outcome of infection. We conclude that topical poly(I:C), as used in this study, was of no benefit in treatment of localized herpes zoster.

Administration, Topical↗
PubMed1975

Evidence for an RNA tumor viruses in human milk.

Certain human milks have been shown to contain particles that have the biochemical and biophysical properties that are diagnostic of the known RNA tumor viruses of animals. These properties include 1) a particle density of 1.16-1.19 g/ml 2) a viral reverse transcriptase (RNA-directed DNA polymerase), and 3) a high molecular weight (HMW) 60-70S RNA that contains polyadenylic regions of 200 nucleotides in length. Inner cores, or nucleoids, of these particles have been isolated. They have a density of 1.26-1.27 g/ml and contain the viral reverse transcriptase and 60-70S RNA. Using molecular hybridization, a specific homology was demonstrated between radioactive DNA synthesized from the RNA of the human milk particle and the RNA from human malignant breast tumors. RNA from benign breast tumors and other human tissues were negative in these tests.

Adenocarcinoma↗
PubMed1975

Continuous negative chest-wall pressure as therapy for severe respiratory distress in older children.

Continuous negative chest-wall pressure (CNP) was used to treat five children, 4 to 11 years of age, who had progressively severe respiratory distress caused by Pneumocystis carinii penumonitis. After initial improvement, two patients developed progressive increases in respiratory rate, alveolar-arterial oxygen gradient, intrapulmonary right-to-left shunt, and hypoxia. The disease ended fatally in both. The remaining three patients continued to improve and recovered from their pulmonary disease. These results show that CNP therapy provides an effective means of improving arterial oxygenation in spontaneously breathing older children, just as in neonates, without the need for endotracheal intubation, prolonged sedation, and muscle relaxants.

Acid-Base Equilibrium↗
PubMed1975

Complete inhibition of adrenocortical responses following sciatic nerve stimulation in rats with hypothalamic islands.

Previous studies from this laboratory have demonstrated that in rats with hypothalamic islands the adrenocortical response to photic and acoustic stimulation was partially inhibited indicating that they were at least to a certain degree neurally mediated, though ether stress produced normal adrenocortical responses. With the purpose of determining to what extent afferent somatosensory connections to the hypothalamus participate in the activation of adrenocortical responses following sciatic nerve stimulation, the effects of this stimulus applied through chronically implanted electrodes were studied on the plasma corticosterone levels in pentobarbital anaesthetized intact animals and in rats with hypothalamic islands. Ether stress or sciatic nerve stimulation for 2 min in intact rats produced a rise of plasma corticosterone to 32.1 plus or minus 1.2 and 32.1 plus or minus 1.8 mug/100 ml, respectively. However, in animals with hypothalamic islands the corresponding values were 29.2 plus or minus 1.8 and 12.4 plus or minus 0.8 mug/100 ml, respectively. The latter value was not significantly different from the basal corticosterone levels (13.0 plus or minus 1.2 mug/100 ml) found in rats 15 min after pentobarbital anaesthesia, the time when the sciatic stimulus was applied. The present data indicate that the adrenocortical discharge following sciatic nerve stimulation is completely inhibited by hypothalamic deafferentation and therefore depends entirely on the activation of the afferent neural pathways to the hypothalamus.

Adrenal Cortex↗
PubMed1975

Adrenocortical responses following sciatic nerve stimulation in rats with partial hypothalamic deafferentations.

Studies from this laboratory have demonstrated that the adrenocortical response following sciatic nerve stimulation is completely inhibited in rats with hypothalamic islands, indicating that this response depends entirely on the activation of afferent neural pathways to the hypothalamus. With the purpose of identifying the site of entry of these neural pathways into the mediobasal hypothalamus the effects of partial hypothalamic deafferentations were studied. It was found that in rats with posterior or posterolateral deafferentation the adrenocortical responses were similar to those obtained in intact rats, while anterior and anterolateral deafferentation resulted in a reduction of 62.3 and 53.3%, respectively. These results would indicate that the sciatic impulses which activate the adrenocortical response involve neural afferents which enter the mediobasal hypothalamus by an anterior pathway.

Adrenal Cortex↗
PubMed1975

Varicella in children with cancer: Seventy-seven cases.

The purpose of this study was to characterize varicella in childhood cancer patients. Seventeen of the 77 patients reviewed were in remission and off all therapy for 3 to 22 months. No one in this group died from varicella or had evidence of visceral dissemination. Among the remaining 60 patients, all of whom were receiving anticancer theapy when they developed varicella, 19 (32%) had visceral dissemination and 4 died, for a mortality rate of 7%. Each of the deaths was associated with primary varicella pneumonitis, with or without acute encephalitis. Visceral dissemination was not related to type or status of malignancy or to duration of specific anticancer therapy. Varicella was more likely to disseminate in children with absolute lymphopenia, less than 500 cells per cubic millimeter, than in patients with higher lymphocyte counts. Cessation of anticancer theapy prior to the onset of lesions appeared to lessen the risk of dissemination. These results show that varicella is more severe in cancer patients on therapy than the general population or in patients who have completed therapy, but is not highly fatal.

Chickenpox↗
PubMed1975

Subacute sclerosing panencephalitis: incidence among ethic groups in Israel.

During the period 1968-73, 46 patients with subacute sclerosing panencephalitis (SSPE), a fatal childhood disease related to rubeola, were encountered in Israel. The incidence per million population was 3.4 for Sephardic Jews, 3.2 for Arabs and only 0.5 for Ashkenazic Jews. An environmental factor which sharply demarcated Arabs and Sephardic Jews from Ashkenazic Jews, and which might account for the differences in incidence of SSPE, was family size: 42.3% of Arab families and 21.5% of the families of Sephardic Jews but only 1.1% of Ashkenazic Jewish families had five or more children. It is postulated that older siblings in large families might constitute vectors which introduce rubeola to the younger siblings at a time when they are at unusual risk of developing SSPE (i.e. before two years of age), whereas in small families, rubeola tends to be acquired later in childhood when the risk of SSPE is reduced.

Adolescent↗
PubMed1975

Bioavailability of acetaminophen suppositories.

Urinary excretion of acetaminophen after rectal administration of three suppository formatulations obtained from hospital and commercial sources was compared to that after oral administration of a tablet dosage form. The absorption of acetaminophen from the suppositories was extremely variable and showed relative bioavailabilities of 68.4 to 87.5% when compared to the oral absorption of the drug from the tablet. The rate of bioavailability differed markedly between products and, in one case, the suppository dose of acetaminophen was so slowly absorbed that the clinical effectiveness of the product is doubtful. The study points out the need for in vivo evaluation of hospital pharmacy manufactured products.

Acetaminophen↗
PubMed1975

Administration in mental health: issues, problems, and prospects.

The mental health field has grown larger and more complex in recent years, but this has not been equalled by increased administrative sophistication. Two problems, neither one irremediable, have contributed to this state of affairs. First, mental health organizations have generally been administered by mental health professionals with little administrative knowledge or training. And second, we have often failed to recognize the very special circumstances faced by administrators in the mental health field. These special circumstances are legion. For one thing, mental health services depend on public funding and must often deal with a high degree of government regulation. For another, the typical staff in a mental health organization is multidisciplinary, professional, and highly autonomous-a bit like a Navy with more admirals than ships. Then too, the transaction between therapist and patient is much more private and intimate in mental health than in most other fields; we are often dealing with a highly dependent patient population; our product is intangible and the success achieved is hard to judge; the boundaries of the field are very hard to define; and the enduring public stigma associated with use of mental health services, combined with the problem of confidentiality, complicates the administrative task. Finally, on top of all this, it is absolutely essential that the mental health administrator understand the need to create and maintain an organizational climate of efficacy and hope. Taken individually, many of these conditions have obvious counterparts in other fields; but taken as a group, they separate mental health from all the other human services, even ones that are closely related. To be effective, therefore, academic programs in mental health administration must reflect these conditions by developing specialized curricula and training procedures.

Attitude to Health↗